INFANT MORTALITY AND PARITY IN RECENT TANZANIAN HISTORY

Dr cand Bonaventure Ngowi, Dept of Statistics, University of Dar es Salaam

ABSTRACT

For the United Republic of Tanzania, the 1948 Census was the earliest operation that can be appropriately described as a demographic enquiry. This operation was conducted in the then Tanganyika nowadays referred to as Tanzania Mainland. For the first in the history of the country questions on mortality and fertility were asked. For every adult female, information was collected on the total number of children born to her, those alive at the census time and whether the deceased had died before of after their first birthday. In the 1957 census the questions on mortality were similar to those asked in the 1948 census (1957 Tanganyika African Census Report, Dar es Salaam, 1963). In the 1967 census more information was collected on the age and sex of recently deceased infants.

Since independence, the United Republic of Tanzania had conducted four population censuses and six demographic and health surveys. The censuses were carried out in 1967, 1978, 1988 and 2002. The last census was carried out after a period of 14 years from the penultimate one which was an awful long period due to the non-availability of funds to pay for the exercise. The first national demographic survey was conducted in 1973 (Henin et al. undated) and the Tanzanian Demographic and Health Surveys were conducted in 1991/92, 1994, 1996,1999 and 2004/2005. The survey for 1994 was called Tanzania: Knowledge, Attitudes and Practices survey and that of 1999 was termed Tanzania: Reproductive and Child Health Survey. These are the major sources of demographic statistics in our country, because the vital events are very incomplete and in some parts of our country it does not exist.

A central proposition of demographic transition theory is the fact that declines in infant and child mortality can encourage subsequent declines in fertility; which occurs only with a lag, but neither theory nor empirical work has explored the extent of such lags. This paper will try to investigate the relationship between infant mortality and parity in the recent Tanzanian history. We will try to link individual perceptions and beliefs about infant mortality risks and their association to health care decision-making and investments in children. We shall try to focus on the individual perceptions of health levels and trends, incorporating infant mortality risks, the overlap of modern and traditional health care systems, the role played by perceived mortality risks and health. Studying of the dynamics of infant mortality is important for several reasons including an understanding of completed family size as well as infant, childhood and maternal mortality differentials.

Studying the dynamics of birth spacing defined as the interval between successive births is of interest for several reasons. First, several inferences are consistent with the notion that in much of the least developed countries, couples having large families tend to space births closer that couples with smaller families. This suggests that the timing of births may be inversely related to completed or cumulative fertility. Furthermore the timing of births has pronounced consequences on infant, child and maternal mortality through the dynamics of sibling competition, maternal depletion and interval effect hypotheses (Hobcraft et al., 1985; Palloni and Millman, 1986; Majumder et al., 1997; Rafalimanana and Westoff, 2000 and Pedersen, 2000). The birth of each successive child creates competition for scarce resources among siblings in the household leading to a lower quality of care and attention to each child. The family resources might be overstretched, increasing the probability of each child in such household becoming malnourished (Gribble, 1993). Physiologically successive births may deplete the mother of energy and nutrition that may lead to pregnancy complications or premature births compounding the risk of infant and maternal deaths, or impair the mother's ability to nurture her children. The early arrival of an infant necessitates the premature weaning of the index child, exposing the weaned child to malnutrition and increasing their probability of contracting infectious and parasitic diseases. Invariably, the longer duration of inter-birth interval has been found to increase profoundly the chances infant survival (Bicego and Ahmad, 1996; Defo, 1997; and Pedersen, 2000).

1.0 INTRODUCTION

There is a need for inter-disciplinary research on the persistent problems of high infant and child mortality and its association with poor health. It is known that initial reductions in infant mortality accounting to 40% or more of all deaths in the least developed countries can often be achieved through advancement in health technology, it is widely more effectively through programs which addresses the socioeconomic, biomedical, environmental and cultural determinants of infant mortality. Their successes in addressing infant maladies hinges on the collaborative efforts of researchers from various fields vis nutritionists, social scientists, demographers, historians, health scientists and educators.

The Eastern Africa and much of sub-Saharan Africa is generally characterized with high rates in infant and child mortality. Until Sri Lanka, Costa Rica, China and the Kerala State of India were shown to be the exceptions to the rule (Halstead et al 1985) low life expectancy and high rates of infant mortality were taken to be the sine qua non for socioeconomic underdevelopment. The performance of these countries corroborated that specific interventions in the provision of health services, nutrition and education can break the economic shackles to improve the health of populations in the least developed countries (Caldwell 1986). It is now accepted that high levels of economic activity based on the high gross domestic product per capita is not imperative in improving the population's health status. The contributions to this end by Primary Health Care (PHC) and Maternal Child Health (MCH) programs and other very specific interventions within this framework (Walsh and Warren, 1986) have acted as catalyst in lowering mortality and improving health in general. However we would like to mention here that much of the changes in sub-Saharan Africa had shown poorest progress, with accelerating declines until 1980 more or less reversed between 1980 and 1990 (Kenneth, 1997).

1.1 THE HISTORICAL BACKGROUND TO THE UNITED REPUBLIC OF TANZANIA

1.1.1 GEOGRAPHY

The United Republic of Tanzania (URT) is the largest country in East Africa, covering 940,000 square kilometers of which 60,000 is inland water. The United Republic of Tanzania (URT) consists of the mainland of Tanganyika officially called Tanzania Mainland and the island of Zanzibar also known as Tanzania Zanzibar. The island of Zanzibar consists of the twin islands of Unguja and Pemba and other much smaller islands. The United Republic of Tanzania lies south of Equator and borders eight countries: Uganda and Kenya to the north; Democratic Republic of Congo, Zambia, Burundi and Rwanda to the west and Mozambique and Malawi to the South.

Tanzania has an abundance of inland water with several rivers and lakes. Lake Victoria or Nyanza is the worlds second largest and drains to the Nile River. Lake Tanganyika runs along the western border and is Africa's deepest and longest freshwater lake, and the world's second deepest lake. Lake Nyasa is in the south of the country. The Rufiji river is Tanzania's largest river and drains to the Indian Ocean south of Dar es Salaam. Although there are many rivers, only the Rufiji and Kagera are navigable by vessels larger than canoes.

One of Tanzania's most prominent geological features is the Great Rift Valley; caused by faulting throughout eastern Africa; and is associated with volcanic activity in the north- eastern regions of the country. There are two branches of the Rift Valley in Tanzania. The western branch holds Lakes Rukwa, Nyasa and Tanganyika; while the eastern branch ends in northern Tanzania and includes Lakes Manyara, Eyasi and Natron.

With the exception of a narrow belt of 900 square kilometers along the coast, most of Tanzania Mainland lies above 200 metres, and much of the country has an altitude of more than 1,000 metres above sea level. In the north Mount Kilimanjaro rises to more than 5,000 metres with a summit of 5,895 metres above sea level at the highest peak, Kibo. This is the highest point in Africa and its peak is snow covered throughout the year at the heart of Equator.

The main climatic feature for the most of the country is the long dry spell from May to October, followed by a period of rainfall from November to April. The main rainy season along the coast and the areas around Mount Kilimanjaro is from March to May, with short rains between October and December. In the western part of the country, around Lake Victoria, rainfall is well distributed throughout the year, with the peak period between March and May.

Administratively, the mainland is divided into 21 regions and Zanzibar into 5 regions. Each region is divided into districts. The mainland regions are divided into 118 districts; while those of Zanzibar are subdivided into 10 districts. Furthermore the districts on the mainland are divided into wards; which in turn are subdivided into villages. The districts in Zanzibar are divided into Shehia; which in turn are subdivided into villages. However due to small number of cases in the 1996 Tanzania Demographic and Health Survey (TDHS); the administrative regions of the United Republic of Tanzania will be collapsed into six cultural and ecological/geographical zones in order to be able to estimate geographic differentials for certain demographic characteristics. This strategy will allow for the necessary geographical comparisons to be made since it will provide relatively large number of cases in each ecological zone and in consequence reduce sampling error. It is prudent to note that this geographical/ecological and cultural zones do not conform to the administrative zones of the United Republic of Tanzania. The classification of regions into zones is as follows: Coastal Zone : (Tanga, Morogoro, Dar es Salaam and Zanzibar), Northern Highland Zone : ( Kilimanjaro and Arusha), Lake Zone : (Kigoma, Tabora, Kagera, Shinyanga, Mara and Mwanza), Central Zone: (Singida and Dodoma), Southern Highland Zone: (Rukwa, Iringa and Mbeya) and Southern Zone: (Ruvuma, Lindi and Mtwara). Here we have considered Zanzibar as one region of the United Republic of Tanzania. These six zones which will be used throughout the study in order to examine ecological; cultural and regional differentials in Infant and Child Mortality.

1.1.2 HISTORY OF THE UNITED REPUBLIC OF TANZANIA

During colonial rule Tanganyika and Zanzibar were two distinct countries. Tanzania Mainland or the former Tanganyika attained her independence from British colonial rule on December 9, 1961. One year later, on December 9, 1962, Tanganyika became a republic, severing all links with the British crown except for her membership in the Commonwealth. Tanganyika was not a colony per se but a mandate territory of which the British were administering the country on behalf of the United Nations Organization.

Zanzibar attained her independence from British rule on December 12, 1963; handed to the minority Arabs under the Sultanate. Zanzibar was a protectorate under the British rule. However on January 12, 1964 the majority of Zanzibaris overthrew the Sultan and created the People's Republic of Zanzibar. Hardly three months later; on April 22, 1964; Presidents Julius Kambarage Nyerere of the Republic of Tanganyika and Sheikh Abeid Amani Karume of the People's Republic of Zanzibar signed Articles of the Union to form the Union of the Republic of Tanganyika and People's Republic of Zanzibar; that is the United Republic of Tanganyika and Zanzibar on April 26, 1964 which was eventually re-named as the United Republic of Tanzania.

1.1.3 THE ECONOMY

Tanzania is one of the least developed countries of the world with mixed type of economy of which agriculture is the backbone of this economy. Agriculture comprises of crop, animal husbandry, forestry, fishery and hunting sub-sectors, contributes substantially to the Gross Domestic Product (GDP).

The Gross Domestic Product increased by 3.9 percent in 1995 according to 1985 prices, compared with 3 percent achieved in 1994 (United Republic of Tanzania, undated). This growth in 1995 did not reach the target of 5 percent predicted in the 1995-98 Economic Recovery Programmes. However it is worthy to note that the economic growth rate attained in 1995 was higher than the predicted population growth rate of 3 percent (United Republic of Tanzania, undated).

1.2 POPULATION AND FAMILY - PLANNING POLICIES AND PROGRAMMES

1.2.1 POPULATION POLICY

After the formation of the Union between Tanganyika and Zanzibar; the United Republic of Tanzania has conducted four population censuses and four demographic and health surveys. The censuses were carried out in 1967, 1978, 1988 and 2002. The first demographic survey was conducted in 1973 (Henin et al, undated), and Tanzania Demographic and Health Survey was carried out in 1991/92, 1996 and 1999. The registration of vital events is incomplete in this country and we cannot rely on them as a major source of demographic statistics.

The 1967 Population Census counted a total of 12.3 million inhabitants. By the 1978 census the population increased to 17.5 implying an annual growth rate of 3.2 percent during the intercensal period 1967-78. The population increased further to 23.1 million by the 1988 census giving an annual growth rate of 2.8 percent for the period 1978-88. By the time of the 2002 Population and Housing Census enumerated a total of 34.6 million giving an annual growth rate of 2.9 percent for the intercensal period 1988-2002. Precisely the population has grown from 12,313,469 persons in the first post-independence census in 1967 to 34,569,232 inhabitants in August 2002. Over this period the population of the United Republic of Tanzania has almost trebled (United Republic of Tanzania, January 2003).

The population density is 39 per square kilometer; which gives the impression that the United Republic of Tanzania is a sparsely populated. The number of people per square kilometer of land area or population density, in the United Republic of Tanzania varies considerably among regions. People are particularly concentrated in Dar es Salaam Region (1793 persons per square kilometer) and Urban West in Zanzibar (1700 persons per square kilometer). Also the other four regions of Zanzibar and Mwanza Region are relatively densely populated (United Republic of Tanzania, January 2003). However the three least densely populated regions are Ruvuma (18 persons per square kilometer); Rukwa (17 persons per square kilometer) and Lindi (12 persons per square kilometer) (United Republic of Tanzania, January 2003).

In the past decade the national economy did not grow significantly due to various reasons, and hence the resources available per head increased by 1 percent annually between 1985 and 1991 (United Republic of Tanzania, undated). In 1992-95, the economy grew at an average of 3.7 and the per capita income grew at an average of 0.8 percent annually (United Republic of Tanzania, undated). However the population grew at a higher rate, and its impact are felt acutely and are vivid on the public budgets for education, health and related fields of human resources development. Hence the improvement of in quality and expansion of these services is unlikely to happen without checking rapid population growth and strengthening the national economy.

It is against this background the National Population Policy was adopted in 1992. The major objective of this policy is to reinforce national development through developing available resources such as the mining sector in order to improve the quality of life of our people. Special emphasis is placed on regulating population growth rate, enhancing population quality and improving the welfare and health of women and children. The major concern of the National Population Policy is to safeguard the satisfaction of the basic needs of the vulnerable groups in the population and develop human resources for current and future national socioeconomic development of the masses. However the United Republic of Tanzania was normally concerned with population issues before the adoption of an explicit population policy; hence she has a tradition of taking on board population issues in her five-year development plans.

On family planning, the goals of the National Population Policy are to strengthen family planning services in order to promote the welfare and health of the individual, family, community and the nation at large eventually reducing the population growth rate. The National Population Policy envisages to make family planning services available at community level to all who want them through the Community Based Distributors (CBD's); encouraging each family to space births at least two years apart and support family life education programmes for youth and family planning for females and males.

2.1THE HEALTH SYSTEM IN TANZANIA

The provision of health services in Tanzania has been the prerogative of the state for a period of almost 30 years. For this period only a limited number of private for profit health services were provided in major towns of the country. After the country attained her independence in 1961, health care facilities were re-directed towards the rural areas were most of the masses were residing and free medical health services were introduced except for Grade I and II. In 1977 provision of private health services for profit was banned under the Private Hospitals (Regulation) Act. This Act barred the practice of medicine and dentistry as a commercial service. This Act had negative implications on the provision of health services in this country.

After a series of major economic and social reforms, the Government adopted different approach to the role of private sector in the society. New policies were promulgated which looked favorably on the role of the private sector. The importance of the private sector in the provision of health care was further recognized with the amendment to the Private Hospitals (Regulation) Act, 1977 which emanated into the establishment of the Private Hospitals (Regulation) (Amendment) Act, 1991. Following the enactment of this act, individual qualified medical practitioners and dentists were allowed to have private – hospitals, with the approval of the Ministry of Health and Social Welfare.

2.1.1 THE DISTRIBUTION OF HEALTH FACILITIES IN THE COUNTRY

The distribution of Health Facilities in the country is biased towards the rural areas since more than 70% of the populace live in these areas. In the past plans for the establishment of any health facility has taken into consideration the facility/population ratio,, but with time this criterion in some areas has been seriously overtaken by the high population growth rate. The distribution of health facilities in the country can be visualized from Table 1 below.

TABLE 1: TYPE OF HEALTH FACILITIES AVAILABLE IN THE UNITED REPUBLIC OF TANZANIA

FACILITY	AGENCY					ROW TOTAL
FACILITY	GOVER-NMENT	PARAS-TATAL	VOLUNTARY/ RELIGIOUS	PRIVATE	OTHERS	ROW TOTAL
Consultant/ Specialized Hospital	4	2	2	0	-	8
Regional Hospital	17	0	0	0	-	17
District Hospital	55	0	13	0	-	68
Other Hospital	2	6	56	20	2	86
Health Centres	409	6	48	16	28	479
Dispensaries	2450	202	612	663	28	3955
Specialized Clinics	75	0	4	22	-	101
Nursing Homes	0	0	0	6	-	6
Private Laboratories	18	3	9	184	-	214
Private X-Ray Units	5	3	2	16	1	27
Column Total	3035	222	746	927	31	4961

Source: Ministry of Health and Social Welfare Abstract 2000

As it can be visualized from Table 1 above most of the health facilities in the country are government owned amounting to 61.18% of them. However the irony is that the government does not own any nursing home.

2.1.1.1 THE STRUCTURE OF HEALTH SYSTEM IN THE COUNTRY

The health system and especially the Government's referral system follows pyramidal pattern of a referral system; recommended by health planners starting from dispensary to Consultant Hospital at the apex (better Health in Africa, 1993). The structure of health services at various levels in the country is outlined below:

Village Health Service

This is the lowest level of health care delivery in the country. Essentially they provide preventive services that can be offered at homes. Essentially each village health post have two village health workers chosen by the village government amongst the villagers and they are given short training before starting the provision of services.

Dispensary Services

Dispensary services are the second stage of health services in the country. The dispensary provides health services to between 6,000 and 10,000 people and should supervise all the village health posts in its ward.

Health Centre Services:

The Health Centre normally caters for 50,000 people that is approximately the population of one administrative division.

District Hospitals:

The most important level in the provision of health services in the country in each district is the District Hospital. Every district in the country is supposed to have a district hospital. For such districts that do not have government owned hospital normally negotiates with religious organizations to designate voluntary/religious hospitals in order to get subventions from the government to contract terms.

Regional Hospitals

Each region is supposed to have a hospital. These regional hospitals offer similar services as those agreed at the district level. However Regional Hospitals have more specialists in various fields and offer additional services that are not provided by the district hospitals.

Referral/Consultant Hospitals

This is the highest level of hospital services in the country and it is found at the apex of the health services pyramid. Currently there are four referral hospitals in the country viz, the Muhimbili National Hospital (MNH) that caters for the eastern zone; Kilimanjaro Christian Medical Centre (KCMC) that caters for the northern zone, Bugando Hospital that caters for the western zone; and Mbeya Hospital that serves the Southern Highlands. Also efforts are underway by Christian Council of Tanzania to built a referral hospital in Dodoma that will cater for the Central zone.

3.1 ANALYSIS OF PARITY IN RECENT TANZANIAN HISTORY

Recently the desired ultimate family planning has gained prominence with the availability of family planning methods. Social and economic perturbations may delay births; for a period but it is likely that the desired family size will be ultimately achieved and the population will tend towards a frequency distribution by the size of the family. Hence changes in fertility and mortality can then be determined as caused by changes in the relative number of low order births or low parity births or changes in the frequency of large families. Parity refers to the number of children previously born alive to a woman. Zero-parity (childless) women are women who have never had a child. One-parity women are women who have had only one child, two-parity women are women who had two children, and so forth. Viewed differently zero-parity women are at the risk of having a first birth, one-parity women of having a second birth, and so forth.

3.1.1 THE RELATIONSHIP BETWEEN INFANT MORTALITY AND PARITY IN RECENT TANZANIAN HISTORY

Apart from the socioeconomic differentials, demographic factors of both the mother and child have been very pronounced on their influence on infant and child mortality. These demographic factors include the sex of the child, age of the mother, parity or birth order, the duration of previous birth interval, and the mother's perception of the size of child at birth. Under normal circumstances female children experience lower mortality than their male counterparts. Also it is expected that lower parity that is parity one and higher parities (parity 7 or higher) will experience higher mortality.

Differences in the risk of infant and childhood deaths across the socio-demographic characteristics of their mothers are very important to identify because they will present us with an opportunity for potential program intervention in order to improve the chances for survival of high risk infants and in essence lower infant mortality. Due largely to heritable factors that lead to greater frailty at birth, male infants are subjected to higher mortality risk than their female counterparts during infancy (early childhood). The least developed countries have high incidences of infant mortality since they have very meager resources. Recent research has shown a less well-known and striking phenomenon of sibling death clustering (Arulampalan and Bhalotra, 2003, 2005). It is clear that across families there are observed and unobserved differences such as genetic frailty, living standards or education which causes infant deaths to cluster within families. Also there is a causal process whereby the death of an infant influences the risk of death of the succeeding child in the same family. Families in which infant deaths are concentrated are poorer or share genetic or environmental risk factors; which expose all the infants to higher death risks. Also the death of an infant causes an increase in the risk of death of the index child in the same family.

A causal process of particular interests operates via the death of an infant by shortening the birth interval. It is known that it can take the mother up to 24 months to recuperate physiologically from birth (da Vanzo and Pebley 1993, Scrimshaw 1996), a short preceding birth interval for the index infant elevates this infant's mortality risks (Hobcraft et al 1983, Cleland and Sathar 1984, Koenig et al 1990, Gribble 1993 and Nath et al 1994). A new pregnancy requires replenishment of vital nutrients such as calcium and iron that are needed to support the development of the foetus. This problem is likely to be much more pronounced in the least developed countries since the bio-availabilty of these nutrients from staples such as cereal is low and nutrient losses associated with infections challenge the capacity of women to produce health infants.

TABLE 2: TRENDS IN INFANT MORTALITY IN ASSOCIATION WITH PARITY

PARITY	91-92 TDHS	1996 TDHS	1999 TRCHS	04-05 TDHS
1	113.3	108.3	130.4	89.0
2-3	93.3	86.1	107.7	74.0
4-6	92.6	82.3	89.8	82.0
7+	105.1	111.9	108.0	94.0

As it can be visualized from Table 2 above we see that infant mortality has been diminishing over the various Demographic and Health Surveys conducted in the United Republic of Tanzania with the exception of the 1999 Tanzania Reproductive and Child Health Survey (TRCHS). This is a good sign that the health programs followed by the government especially the Primary Health Care Initiative and the Maternal and Child Health programs are producing the required effect in lowering infant mortality. From the table above we see that infant mortality rates for parity one births and those of parity seven and more are much higher than those of parties 2-3 and 4-6. However we note that the female sample size for the 1999 TRCHS was very small, hence results from the analysis of such data should be taken with caution.

Also as it can be observed from Table 2 above, the rates of infant mortality for parities 2-3 and 4-6 have been decreasing over the years but the Government of the United Republic of Tanzania has a long way to go before we reach the millennium development goals or rather single digits in infant mortality rates. However we note that large differentials in risks of mortality and to lesser extent morbidity have been observed by the age of the infant or child. As the age of the infant increases there is a rapid reduction of the risks of mortality. This is normally associated with the changing morbidity patterns by age that is incidence and the changing relationship between morbidity and mortality by age that can be termed as case fatality.

Maternal and Child Health Care (MCH Care) encompasses specific interventions that are aimed at the health status of the children and their mothers. The MCH program is specifically concerned with the biological demands of reproduction, growth and development, and the vulnerability of the mothers and their children as a result of those demands. Tanzania has realized commendable achievements in extending the coverage of MCH Care and this has resulted in improved utilization of the care that has resulted in lowering infant mortality as it can be depicted in Table 2 above.

4.0 CONCLUSION

We have seen in this paper that parity has been associated with infant mortality. The first born and high-parity infants had higher mortality than infants of parities 2 to 6 and this has been the trend over all Demographic and Health Surveys carried in the United Republic of Tanzania. Mortality rates are generally higher for boys than for girls. However we would like to note here that the government has a long way to go before we achieve the millennium development goals in the reduction of the rates of infant mortality or achieve single digits. Therefore there is a need for the government to build more referral hospitals for other zones to complement the existing four. Also there is a need for the government to build a specialized hospital to deal with congenital heart diseases since these maladies are very rampant among infants and their treatment needs special equipments which are not available in the country and patients must be taken abroad for treatment. Therefore I would like to ask the more developed countries and in particular the Group of 8 that the most industrialized countries of the world to help Tanzania in achieving this goal since a substantial number of infants are dying due to congenital malformations and our hospitals cannot even provide proper diagnosis. There is a need to study the aetiological factors associated with congenital malformations in infants; that contributes heavily to infant mortality rates in the United Republic of Tanzania in the twenty first century given the advancements in science and technology. I would like to call the Most Industrialized Countries to help the poor countries to eradicate this scourge from the world.

In this paper we have shown that infant mortality is of great concern to the governments and policy makers who normally strive to allocate their meager resources in implementing health programs that are aimed at reducing infant mortality to acceptable levels. Studies have shown that in developing countries, deaths at infancy accounts for a large proportion of the total deaths of infants before they reach their first birthday. Hence efforts in reducing deaths in infancy will go a long way in reducing the general level of mortality. It was also noted that the probabilities of male infants dying was higher than that for females and the magnitude of variance differs from population to population.

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